Stabilization of oleaginous materials



Patented Feb. 22, 1949 STATE RATENE @FFEQE STABELHZATIION i? GILEAGENGHJS MATEREAL Frank A. Norris, Minneapolis, Minn assigncr to General Mills, Inc, a corporation oi? Delaware No Drawing. Application Beccinber'li, 19%, Serial No. 568,243

found that combinations of certain antioxidants produce a resultant stability far in excess of the sum of the stebilities obtained by the use of the compounds singly.

It is therefore a primary object of the present invention to provide a process of stabilizing fatty or oleaginous materials against oxidation and the development of rancidity.

It is another object of the invention to provide products containing fats or oils which are stabilized against oxidation and the development of rancidity.

A further object of the invention is to provide a process of stabilizing fatty or oleaginous prod ucts of animal cri -in by means of antioxidants which exhibit synergistic effects.

These and other objects of the invention will be apparent from the following description of the invention with particular reference to specific ex amples which are to be understood as illustrative only and not as limiting the invention.

It has been found that a synergistic antioxidant efiect is obtained by the conjoint use of cafieic acid and componcls containing the ene-diol group noo=c-on) such as l-ascorbic acid. While ascorbic acid, which is water-soluble, has been known to have antioxidant effect in aqueous media, it has not been particularly effective in fats, probably because of its extremely low solubility. Caileic acid, on the other hand, has an appreciable antioxidant effect in fatty media. It has been found, however, that when these two compounds are used together, they exhibit a pronounced synergistic efl'ect which give the oleaginous material in which they are incorporated a stability Iar in excess of that of the untreated material and far in excess of the sum of the individual stabilities contributed when each of these compounds is used alone.

This is demonstrated by the following table showing the efiect of these antioxidants on prime steam lard.

Swift Protective sample gggg Factor 1 Prime Steam Lard 1 2 (1)+0.0l5% cefieic acid 48 48 3 Prime Steam Lard. 2. 6 4 (3)+0.03% pnmino-benzoic acid-less than... 2.3 1 5 (3)+0.05% l-ascorbic acid-less than.-. 11. 6 4. 6 6 Prime Steam Lnrd 3.8 7 (6)+0.03% p-amlno-benzoic acid-{- 0.05% l-ascorbic acid 32 8.6 8 (6) +0.08% p-umino-benzoic acid-{- 0.05% l-ascorbic acid+0.0i6% csfieic acid 307. 5 B1 In place of l-ascorbic acid other compounds having the ene-diol groups such as reductone, dilly droxymaleic acid, analogues or isomers of ascorbic acid, such as isoascorbic acid, glucoascorbic acid, araboascorbic acid, etc., may be used.

The prime steam lard employed was the article available on the market, and it was used in these tests without any additional purification. Hydrogenation of this impure material results in a decicled increase in stability. However, for the purpose of these tests, the material was not hydrogenated in. view of the fact that even without hydrogenation the time required for some of the tests was prolonged for weeks because of the hi h stabilities. It will be apparent, therefore, that the process may be employed on other materials hawing originally higher or lower stabilities, in which case it may be desirable to reduce or increase the amount of antioxidant added.

Instead of the amounts of antioxidants shown above, it is possible to employ decidedly lower concentration where such a high stability is not necessary or desirable. The lower limit of antioxidant to be added appears to be dictated by the' In addition to its effect on the antioxidant properties of the product, p-amino-benzoic acid has decided preservative action and represses microbiological" growth. The common materials employed to inhibit oxidative rancidity have no effect on microbiological growth. Consequently yeast, molds, and the like, continue to grow and produce hydrolytic or other enzymic changes which result in rancidity. Thus, while the rancidity so produced is a distinct disadvantage in itself, the presence of large numbers of microorganisms is an even greater disadvantage in view of the possible ill effect on those who consume such a product.

It is apparent that these various objections of the prior art are overcome by the present invention in that it inhibits both oxidative rancidity and microbiological growth, Hydrolytic and enzymic rancidity are likewise inhibited in view of the inhibition or microbiological growth. Moreover, all of the substances are non-toxic and the p-amino-benzoic acid and l-ascorbic acid are recognized vitamins which perform additional functions when consumed.

It is also to be understood that the invention may be applied to animal oils or fats of any.

nature whether edible or not. all of which products-are contemplated by the term oleaginous material of animal origin" as used in the appended claims.

I claim as my invention:

1. A composition of matter comprising an oleaginous material of animal origin containing, and belngstabilized against the development of rancidity by, not substantially in excess of onetenth per cent of each of l-ascorbic acid, pamino-benzoic acid, and caffeic acid.

2. A composition of matter comprising an oleaginous material of animal origin containing, and being stabilized against the development of rancidity by, not substantially in excess of .1 per cent of each of a compound containing an enediol group, p-amino-benzoic acid, and cafieic acid.

3. A process of stabilizing an oleaginous material of animal origin which comprises incorporating therein, not substantially in excess of onetenth per cent of each of l-ascorbic acid, pamino-benzoic acid, and caffeic acid.

4. A process of stabilizing an oleaginous material ofanimal origin which comprises incorporating therein, not substantially in excess of .1 per cent of each of a compound containing an enediol.i group. D-amino-benzoic acid, and cafleic aci i 5. An edible shortening containing an oleaginous material of animal origin, and being stabilized against the development of rancidity by, not substantially in excess 01' .1 r cent of each 01 l-ascorbic acid. p-amino-benzoic acid, and cafleic acid.

6. A composition or matter comprising an ole-v aginous matter of animal origin containing, and

being stabilized against the development of rancidity by, approximately 0.03% p-alnino-benzoic acid, 0.05% of a compound containing an enediol group, and 0.015% cafieic acid.

7. A composition of matter comprising an oleaginous matter 01' animal origin cmtaining, and being stabilized against the development oi rancidity by, approximately 0.03% p-amino-benzoic acig, 0.05% of l-ascorbic acid, and 0.015% cail'eic ac 8. A process oi stabilizing an oleaginous material oi. animal origin which comprises incorporating therein, approximately 0.03% p-amino-benzoic acid, 0.05% of a compound containing an ene-diol group, and 0.015% caffeic acid.

9. A process of stabilizing an oleaginous material 01 animal origin which comprises incorporating therein, approximately 0.03% p-amino-benzoic acid, 0.05% of l-ascorbic acid, and 0.015% caffeic acid.

FRANK A. NORRIS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Date Number Name 1,975,755 Hoyt et al Oct. 2, 1934 1,996,717 Carlisle Apr. 2, 1935 2,159,986 Gray et al May 30, 1939 2,333,657 Mattill et al Nov. 9, 1943 OTHER REFERENCES 

